BRANDON – GPS languished in the background for more than a decade until Outback showed that satellites steer farm implements better than people.
Once GPS guidance gained a foothold, everyone assumed the next big benefit would be variable rate nitrogen.
“I totally question that assumption,” says Dan Hacault. The Swan Lake, Man., farmer raised eyebrows in the crowd at a recent AgriTrend field day in Brandon when he said that three years of diligent variable rate nitrogen had given him no financial benefit. But it was educational, he says.
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“Variable rate didn’t save me any input money or make any extra money, but it did identify problem areas in our fields. Now we can start to deal with those areas.
“We had saline areas, but we never had any idea how bad they were from the soil tests. And we found some areas with nutrient deficiencies.”
He says by using the yield curve concept from Rigas Karamanos, he saw little could be gained with nutrient management on his farm.
“If I’m going to make any kind of variable rate pay, it has to be a total package, not just fertilizer.”
Developed by Viterra’s Karamanos, the yield curve provides producers a visual guide to the points where fertilizer application rates are justified by increased costs of the added nutrients.
As applications of nutrients such as nitrogen in a specific crop, soil type and location are increased, revenue benefits will only climb to a certain level before the cost of the fertilizer begins to erode the profits.
In applying the yield curve, Hacault says it became apparent that a financial return on variable rate depends on many factors, including nutrient cost, equipment cost, crop value and especially the potential productivity of the land.
“It all comes down to basic agronomics. Unless you plug in all the factors and have some way of measuring them, you’re going nowhere with variable rate. You must be able to determine your return on investment.”
Hacault says satellite imagery is important in putting together a good plan, but it must be recent and high resolution. He has one field where the most recent satellite photo is six years old. Cloud cover and timing issues have prevented him from getting a good image. He says old images have little value for farmers planning a fungicide application.
On the other hand, some of his fields have weekly, high resolution photos with one metre pixels.
Hacault uses the agronomic services of his local Pembina Co-op. They have been fortunate in obtaining these high resolution photos on a website run by North Dakota potato farmers, who pay for the high quality images on a regular basis. Because his farm is located close to the North Dakota border, the shots include his land.
“Real time images are important, especially when you’re applying expensive fungicides or insecticides. I think that’s where the remote control Cropcam will become a valuable tool for farmers. You can fly the field one day and have an accurate and relevant prescription map ready the next day for spraying.”
On the morning of the July 23 field day, GIS specialist Simon Knutson was able to obtain a fresh 30 metre satellite image taken the previous day. The photos included the canola field where the afternoon demos took place.
By the time the afternoon session started, the morning photos had been digitally developed into a prescription map depicting areas of the field that required various rates of fungicide.
“That’s the kind of real time information farmers need to make good decisions,” Hacault said. He added there are other motivators for variable rate lurking on the horizon.
“Accountability is coming. It’s just a matter of time. The government responds to the voters and the voters think farmers are polluters. There will be legislation on crop nutrient inputs. We can fight it all we want, but it’s coming.
“We have to start now to change the way we grow crops. The correct amount of nutrients. Correct placement of nutrients. Correct timing.
“Variable rate based on crop requirements will become mandatory. There’s no other way we can handle it. I don’t see a choice.”
For more information, contact Dan Hacault at dhacault@inetlink.ca.
